• 제목/요약/키워드: Flame test

검색결과 543건 처리시간 0.025초

케이블 화재의 화염전파 해석을 위한 FDS 모델의 격자민감도 평가 (Assessment of Grid Sensitivity in the FDS Field Model to Simulate the Flame Propagation of an Electric Cable Fire)

  • 김성찬;이성혁
    • 한국안전학회지
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    • 제23권4호
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    • pp.30-35
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    • 2008
  • The present study has been conducted to examine the effect of grid resolution on the predicted results for electric cable fire using pyrolysis model in FDS(Fire Dynamics Simulator, version 5). The grid independent test for different grid resolutions has been performed for a PE coating cable and the grid resolution is defined by the non-dimensional characteristic length of fire and mean grid size. The calculated maximum heat release rate and mean flame spread rate were almost constant for higher grid resolution of 20${\sim}$25 and the computing time for the grid resolution takes approximately 20hours to solve flame propagation with pyrolysis model. The geometrical simplification of a electric cable dose not greatly affect on the maximum heat release rate and flame spread rate and the rectangular approximation of cable shape gives acceptable result comparing with the round cable with stepwise grid.

삼파장 적외선식 불꽃감지기의 자가진단 회로 개발 (A Study on Signal Circuit of the Self Diagnosis Type Triple Infrared Flame Detector)

  • 송현선;이의용
    • 조명전기설비학회논문지
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    • 제27권10호
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    • pp.69-74
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    • 2013
  • There is needed the triple pyroelectric Infrared flame detector to really recognize problem, for the prevention and early suppression of fire. This system recognizes the characteristics of fire sources in various type and is communicated the message to the operators. Therefore, the prevention and early suppression of fire is available. Especially this paper focuss on development of the self diagnosis type flame detector for preventing malfunction comparing of basic and detected values.

트리브로모 변성폴리에스테르를 함유한 PU 난연도료의 합성과 도막 특성화 (Synthesis and Characterization of PU Flame-Retardant Coatings Using Tribromo Modified Polyesters)

  • 박은경;양인모;김대원;황규현;박홍수
    • 폴리머
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    • 제25권3호
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    • pp.391-398
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    • 2001
  • 난연성분인 트리브로모아세트산의 함량을 10, 20, 30wt%로 변화시키면서 1,4-부탄디올, 아디프산 및 트리메틸올프로판과 축합중합을 하여 트리브로모 변성폴리에스테르(TBAO)를 합성한 후에, TBAO류와 이소시아네이트를 블렌드하여 2성분계 폴리우레탄(PU) 난연도료를 제조하였다. 제조된 난연도료의 도막물성을 측정한 결과, 결코 비난연도료보다 물성이 저하되지는 않았다. 또한 난연도료의 난연성 시험결과, 수직법에서 트리브로모아세트산 20 wt%에서 불꽃에 타지 않아서 양호한 난연도료임을 알 수 있었다.

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제트확산화염에서의 불활성기체 소화농도 (Flame- Extinguishing Concentrations of Inert Gases in Jet Diffusion Flames)

  • 지정훈;이의주
    • 한국안전학회지
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    • 제24권1호
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    • pp.21-25
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    • 2009
  • Extinguishing limits of laminar ethylene/oxygen flames in both normal and inverse co-flow jet burner have been determined experimentally and computationally. An inert gas($N_2$, Ar, $CO_2$) was added into the oxidizer to find the critical concentration and the effectiveness of the agents on flame extinction. The experimental results showed that the physical aspect of inert gases was main mechanism for flame blow-out as same as cup burner test, but the flow effect should be considered to determine the extinction concentration. The numerical prediction was performed with modified WSR model and the result was in good agreement with the measurements. The experimental and numerical methods could be used for the assessment of various flame suppression agents such as minimum extinguishing concentration.

분할연소기의 화염 가시화 연구 (Flmae Visualization of the sector combustor)

  • 김보라미;최채홍;김춘택;최성만
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2009년도 제33회 추계학술대회논문집
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    • pp.213-216
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    • 2009
  • 가스터빈 연소기의 화염 특성을 알기 위하여 분할 연소기 시험을 수행하였다. 점화시험은 여러 가지 연소기 유입 공기속도와 공기과잉율에 따라 토치 점화장치를 이용하여 수행되었다. 또한, 연료를 충분히 공급한 상태에서 점화를 수행한 후 점차 연료량을 감소시켜가며 희박연소한계를 측정 하였다. 실험 결과, 공기과잉율 6에서 안정한 점화를 보였고 이 값은 연소기 공기 유입속도에 따라 점점 증가함을 보였다. 최소 실화한계는 연소기 공기 유입속도 40 m/s에서 약 4였고, 이 값 또한 연소기공기유입속도에 따라 약 10 까지 증가함을 보였다.

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나노클레이 첨가에 따른 할로겐프리 난연컴파운드의 기계적 특성에 관한 연구 (A Study on Mechanical Properties Improvement of Halogen-free Flame Retardant Compounds by Nanoclay Addition)

  • 황찬연;양종석;성백용;김지연;박대희
    • 한국전기전자재료학회논문지
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    • 제28권2호
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    • pp.126-130
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    • 2015
  • In this study, some materials are organized and experimented with variables to obtain the optimum mix proportion for the mechanical property of halogen free flame resistance compound with varying addition of nano clay. Tensile strength, density and stiffness are tested in the room temperature. In this study, unlike existing layered structure, nano clay with tabular structure is used and sufficient stiffness, strength, thermal stability and gas block capability can be achieved with small amount of addition. Tensile strength and elongation test show high rupture strength only in specimens with compatibilizing agents while density test shows average measurement in all the specimens except T-9. It was confirmed that the measurement value according to the additives in compatibilizing agent or in nano clay of hardness test represents similarly.

보강성 충진제를 첨가한 실리콘 고무의 난연 및 화재안전 특성에 관한 연구 (A Study on the Properties of Flame Retardant and Fire Safety of Silicone Rubbers Added Reinforcing Fillers)

  • 박승호;이성일
    • 한국전기전자재료학회논문지
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    • 제32권4호
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    • pp.349-355
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    • 2019
  • A fire, be it caused intentionally or unintentionally, leads to economic loss and physical damage, and requires digestion. The number of fires is increasing yearly, and electrical fires account for more than 30% among the main causes of fires. Electric wires that catch fire typically employ silicone coatings; silicone has organic as well as inorganic properties. Silicon is a natural, nonexistent, synthetic product with numerous applications. In this study, a silicon rubber for application in wires was prepared by high-temperature vulcanization (HTV) with a Shore A hardness of 70. We report results for the flame retardancy test and the fire safety characteristics via inorganic analysis. For this, a quartz inorganic material was added to the wire specimen, and 18% powdered extinguishing agent ammonium phosphate and expanded vermiculite respectively. Thus, expanded vermiculite showed the best flame retardancy and fire safety characteristics.

가스터빈 연소기 기본형상 결정에 관한 연구 (A Study on the Preliminary Design of Gas Turbine Combustor)

  • 안국영;김한석;김관태;배진호
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 1997년도 제15회 KOSCO SYMPOSIUM 논문집
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    • pp.135-151
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    • 1997
  • The preliminary design and performance test for determining dimensions of gas turbine combustor were investigated. The combustor design program was developed and applied to design our combustor. and detailed design for determining of swirler. dome and liner holes were performed experimentally. The swirler. which govern the combustion characteristics of combustor, was determined $40^{\circ}$ as swirl angle at first performance test. After second performance test the swirler was re-determined by 24 mm i.d.. 34 mm o.d., and swirl angle of $45^{\circ}$. The geometry of liner holes were determined by considering the flame stability and recirculation zone size. It was found that flame can be more easily stabilized by adjusting the swirier dimensions rather than liner holes. The geometry of swirler and liner holes were re-determined by final performance test with dilution holes. Also. the performance of combustor was evaluated by analysis of exhaust gases.

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세라믹 溶射皮膜의 强度向上에 관한 硏究

  • 김영식;배차헌;김영식
    • Journal of Welding and Joining
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    • 제9권3호
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    • pp.18-25
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    • 1991
  • The purpose of this paper was to investigate the effect of deposition configuration on the mechanical properties of the flame sprayed titania ceramic coating. The sprayed deposition configuration was made in different five types with titania ceramic and Ni-base alloy on the mild steel substrate. The composite coating exhibited superior mechanical properties such as hardness, adhesive strength, thermal shock resistance and corrosion resistance, whereas the mixed coating proved to be more resistant to erosion. Especially graded coating, which consist of Ni-base alloy undercost, intermediate grade coat and titania ceramic overcost, showed excellent mechanical properties.

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멜라민이 코팅된 수산화마그네슘 입자의 제조와 그 복합입자의 난연특성 (Preparation of Mg(OH)2-Melamine Core-Shell Particle and Its Flame Retardant Property)

  • 임형미;윤준호;정상옥;이동진;이승호
    • 한국재료학회지
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    • 제20권12호
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    • pp.691-698
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    • 2010
  • Magnesium hydroxide-melamine core-shell particles were prepared through the coating of melamine monomer on the surface of magnesium hydroxide in the presence of phosphoric acid. The melamine monomer was dissolved in hot water but recrystallized on the surface of magnesium hydroxide by quenching to room temperature in the presence of phosphoric acid. The core-shell particle was applied to low-density polyethylene/ ethylene vinyl acetate (LDPE/EVA) resin by melt-compounding at $180^{\circ}C$ as flame retardant. The effect of magnesium hydroxide and melamine content has been studied on the flame retardancy of the core-shell particles in LDPE/EVA resin according to the preparation process and purity of magnesium hydroxide. Magnesium hydroxide prepared with sodium hydroxide rather than with ammonia solution revealed higher flame retardancy in core-shell particles with LDPE/EVA resin. At 50 wt% loading of flame retardant, core-shell particles revealed higher flame retardancy compared to that of the exclusive magnesium hydroxide in LDPE/EVA composite, and it was possible to satisfy the V0 grade in the UL-94 vertical test. The synergistic flame retardant effect of magnesium hydroxide and melamine core-shell particles was explained as being due to the endothermic decomposition of magnesium hydroxide and melamine, which was followed by the evolution of water from the magnesium hydroxide and porous char formation due to reactive nitrogen compounds, and carbon dioxide generated from melamine.